mavlink: add MavlinkULog class to receive ulog data from the logger

src/modules/mavlink/CMakeLists.txt

@@ -49,6 +49,7 @@ px4_add_module(
 		mavlink_ftp.cpp
 		mavlink_log_handler.cpp
 		mavlink_shell.cpp
+		mavlink_ulog.cpp
 	DEPENDS
 		platforms__common
 	)

src/modules/mavlink/mavlink_ulog.cpp

@@ -0,0 +1,216 @@
+/****************************************************************************
+ *
+ *   Copyright (c) 2016 PX4 Development Team. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name PX4 nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/**
+ * @file mavlink_ulog.cpp
+ * ULog data streaming via MAVLink
+ *
+ * @author Beat Küng <beat-kueng@gmx.net>
+ */
+
+#include "mavlink_ulog.h"
+#include <px4_log.h>
+#include <errno.h>
+
+bool MavlinkULog::_init = false;
+MavlinkULog *MavlinkULog::_instance = nullptr;
+sem_t MavlinkULog::_lock;
+
+
+MavlinkULog::MavlinkULog()
+{
+	_ulog_stream_sub = orb_subscribe(ORB_ID(ulog_stream));
+
+	if (_ulog_stream_sub < 0) {
+		PX4_ERR("orb_subscribe failed (%i)", errno);
+	}
+	_waiting_for_initial_ack = true;
+	_last_sent_time = hrt_absolute_time(); //(ab)use this timestamp during initialization
+}
+
+MavlinkULog::~MavlinkULog()
+{
+	if (_ulog_stream_ack_pub) {
+		orb_unadvertise(_ulog_stream_ack_pub);
+	}
+	if (_ulog_stream_sub >= 0) {
+		orb_unsubscribe(_ulog_stream_sub);
+	}
+}
+
+void MavlinkULog::start_ack_received()
+{
+	if (_waiting_for_initial_ack) {
+		_last_sent_time = 0;
+		_waiting_for_initial_ack = false;
+		PX4_DEBUG("got logger ack");
+	}
+}
+
+int MavlinkULog::handle_update(mavlink_channel_t channel)
+{
+	static_assert(sizeof(ulog_stream_s::data) == MAVLINK_MSG_LOGGING_DATA_FIELD_DATA_LEN, "Invalid uorb ulog_stream.data length");
+	static_assert(sizeof(ulog_stream_s::data) == MAVLINK_MSG_LOGGING_DATA_ACKED_FIELD_DATA_LEN, "Invalid uorb ulog_stream.data length");
+
+	if (_waiting_for_initial_ack) {
+		if (hrt_elapsed_time(&_last_sent_time) > 3e5) {
+			PX4_WARN("no ack from logger (is it running?)");
+			return -1;
+		}
+	}
+
+	// check if we're waiting for an ACK
+	if (_last_sent_time) {
+		bool check_for_updates = false;
+		if (_ack_received) {
+			_last_sent_time = 0;
+			check_for_updates = true;
+		} else {
+
+			if (hrt_elapsed_time(&_last_sent_time) > ulog_stream_ack_s::ACK_TIMEOUT * 1000) {
+				if (++_sent_tries > ulog_stream_ack_s::ACK_MAX_TRIES) {
+					return -ETIMEDOUT;
+				} else {
+					PX4_DEBUG("re-sending ulog mavlink message (try=%i)", _sent_tries);
+					_last_sent_time = hrt_absolute_time();
+					mavlink_logging_data_acked_t msg;
+					msg.sequence = _ulog_data.sequence;
+					msg.length = _ulog_data.length;
+					msg.first_message_offset = _ulog_data.first_message_offset;
+					memcpy(msg.data, _ulog_data.data, sizeof(msg.data));
+					mavlink_msg_logging_data_acked_send_struct(channel, &msg);
+				}
+			}
+		}
+
+		if (!check_for_updates) {
+			return 0;
+		}
+	}
+
+	bool updated = false;
+	int ret = orb_check(_ulog_stream_sub, &updated);
+	while (updated && !ret) {
+		orb_copy(ORB_ID(ulog_stream), _ulog_stream_sub, &_ulog_data);
+		if (_ulog_data.flags & ulog_stream_s::FLAGS_NEED_ACK) {
+			_sent_tries = 1;
+			_last_sent_time = hrt_absolute_time();
+			lock();
+			_wait_for_ack_sequence = _ulog_data.sequence;
+			_ack_received = false;
+			unlock();
+
+			mavlink_logging_data_acked_t msg;
+			msg.sequence = _ulog_data.sequence;
+			msg.length = _ulog_data.length;
+			msg.first_message_offset = _ulog_data.first_message_offset;
+			memcpy(msg.data, _ulog_data.data, sizeof(msg.data));
+			mavlink_msg_logging_data_acked_send_struct(channel, &msg);
+
+		} else {
+			mavlink_logging_data_t msg;
+			msg.sequence = _ulog_data.sequence;
+			msg.length = _ulog_data.length;
+			msg.first_message_offset = _ulog_data.first_message_offset;
+			memcpy(msg.data, _ulog_data.data, sizeof(msg.data));
+			mavlink_msg_logging_data_send_struct(channel, &msg);
+		}
+		ret = orb_check(_ulog_stream_sub, &updated);
+	}
+
+	return 0;
+}
+
+void MavlinkULog::initialize()
+{
+	if (_init) {
+		return;
+	}
+	sem_init(&_lock, 1, 1);
+	_init = true;
+}
+
+MavlinkULog* MavlinkULog::try_start()
+{
+	MavlinkULog *ret = nullptr;
+	bool failed = false;
+	lock();
+	if (!_instance) {
+		ret = _instance = new MavlinkULog();
+		if (!_instance) {
+			failed = true;
+		}
+	}
+	unlock();
+
+	if (failed) {
+		PX4_ERR("alloc failed");
+	}
+	return ret;
+}
+
+void MavlinkULog::stop()
+{
+	lock();
+	if (_instance) {
+		delete _instance;
+		_instance = nullptr;
+	}
+	unlock();
+}
+
+void MavlinkULog::handle_ack(mavlink_logging_ack_t ack)
+{
+	lock();
+	if (_instance) { // make sure stop() was not called right before
+		if (_wait_for_ack_sequence == ack.sequence) {
+			_ack_received = true;
+			publish_ack(ack.sequence);
+		}
+	}
+	unlock();
+}
+
+void MavlinkULog::publish_ack(uint16_t sequence)
+{
+	ulog_stream_ack_s ack;
+	ack.timestamp = hrt_absolute_time();
+	ack.sequence = sequence;
+
+	if (_ulog_stream_ack_pub == nullptr) {
+		_ulog_stream_ack_pub = orb_advertise_queue(ORB_ID(ulog_stream_ack), &ack, 3);
+
+	} else {
+		orb_publish(ORB_ID(ulog_stream_ack), _ulog_stream_ack_pub, &ack);
+	}
+}

src/modules/mavlink/mavlink_ulog.h

@@ -0,0 +1,126 @@
+/****************************************************************************
+ *
+ *   Copyright (c) 2016 PX4 Development Team. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name PX4 nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/**
+ * @file mavlink_ulog.h
+ * ULog data streaming via MAVLink
+ *
+ * @author Beat Küng <beat-kueng@gmx.net>
+ */
+
+#pragma once
+
+#include <stddef.h>
+#include <stdint.h>
+#include <px4_tasks.h>
+#include <px4_sem.h>
+#include <drivers/drv_hrt.h>
+
+#include <uORB/topics/ulog_stream.h>
+#include <uORB/topics/ulog_stream_ack.h>
+
+#include "mavlink_bridge_header.h"
+
+/**
+ * @class MavlinkULog
+ * ULog streaming class. At most one instance (stream) can exist, assigned to a specific mavlink channel.
+ */
+class MavlinkULog
+{
+public:
+	/**
+	 * initialize: call this once on startup (this function is not thread-safe!)
+	 */
+	static void initialize();
+
+	/**
+	 * try to start a new stream. This fails if a stream is already running.
+	 * thread-safe
+	 * @return instance, or nullptr
+	 */
+	static MavlinkULog *try_start();
+
+	/**
+	 * stop the stream. It also deletes the singleton object, so make sure cleanup
+	 * all pointers to it.
+	 * thread-safe
+	 */
+	void stop();
+
+	/**
+	 * periodic update method: check for ulog stream messages and handle retransmission.
+	 * @return 0 on success, <0 otherwise
+	 */
+	int handle_update(mavlink_channel_t channel);
+
+	/** ack from mavlink for a data message */
+	void handle_ack(mavlink_logging_ack_t ack);
+
+	/** this is called when we got an vehicle_command_ack from the logger */
+	void start_ack_received();
+
+private:
+
+	MavlinkULog();
+
+	~MavlinkULog();
+
+	static void lock()
+	{
+		do {} while (sem_wait(&_lock) != 0);
+	}
+
+	static void unlock()
+	{
+		sem_post(&_lock);
+	}
+
+	void publish_ack(uint16_t sequence);
+
+	static sem_t _lock;
+	static bool _init;
+	static MavlinkULog *_instance;
+
+	int _ulog_stream_sub = -1;
+	orb_advert_t _ulog_stream_ack_pub = nullptr;
+	uint16_t _wait_for_ack_sequence;
+	uint8_t _sent_tries = 0;
+	volatile bool _ack_received = false; ///< set to true if a matching ack received
+	hrt_abstime _last_sent_time = 0; ///< last time we sent a message that requires an ack
+	ulog_stream_s _ulog_data;
+	bool _waiting_for_initial_ack = false;
+
+	/* do not allow copying this class */
+	MavlinkULog(const MavlinkULog &) = delete;
+	MavlinkULog operator=(const MavlinkULog &) = delete;
+};